8287210 Long-term association between job strain and all-cause and cardiovascular mortality: a 23-year follow-up of pooled cohorts in Northern Italy

<h3>Objective</h3> To investigate the association between high job strain (high-JS) and all-cause and cardiovascular (CVD) mortality over a long period in Northern Italian population- and worker-based cohorts, overall and across occupational classes. <h3>Material and Methods</h3> We studied 9554 workers aged 30-59 years (55% females), recruited from 1986 to 1994 and followed-up for 25 years. Risk factors assessment followed WHO-MONICA protocols. Death certificates were retrieved to identify all-cause and CVD deaths. Occupational classes (OC) were aggregated as ‘managers/proprietors’ (MP), ‘non-manual’ (NW), and ‘manual’ (MW) workers. The Job Content Questionnaire (JCQ) scores were used to classify workers for high-JS. Generalized linear models were used to estimate sex- and age-adjusted mortality rates, Cox proportional-hazards models to estimate sex-, age-, occupational class-, previous CVD-, and major CVD risk factors-adjusted Hazard Ratios (HR) for high-JS (non high-JS as reference) exposure overall and, based on interaction test, across OCs. <h3>Results</h3> A total of 794 all-cause and 176 CVD deaths occurred in a median follow-up of 23 years. All-cause mortality rates across JCQ categories ranged from 2.50 events/1000 py (active) to 3.31 (passive), CVD mortality rates from 0.51 (low-JS) to 0.71 (high-JS). In the adjusted Cox models, high-JS was not associated with all-cause mortality (HR; 95%CI: 1.06; 0.91-1.25) but showed a significant association with CVD mortality (1.46; 1.04-2.04). The OCs showed similar all-cause mortality rates (MP=3.50/1000 py, NW=2.37, MW=2.96; p=0.14) but different CVD mortality rates (MP=0.94/1000 py, NW=0.42, MW=0.60; p=0.04). The HRs for high-JS were consistent across OCs for CVD mortality: the interaction term was not significant (p=.66). <h3>Conclusion</h3> Exposure to high-JS has a long-term association with CVD mortality, going beyond the working period. This association is consistent across OCs. Interventions addressing workplace psychosocial stressors are warranted.